Practical Properties Guide

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Current by Gerardo Capiel
on Mar 05, 2014 11:37.

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h2. Properties Preface

We have two main properties, accessMode and mediaFeature accessibilityFeature that have a wide range of values. Only a subset of these values are relevant for any specific media type. Since one of the most common questions we face is "how do I tag this with schema.org tags... what's the object and the properties I should use?", this page expresses that in an easily consumed fashion. I am formatting this in a wiki for now, to get the information out and available as we refine this. Once it is stable, we can format it into a better presentation method. (Matt and I have proven that Wordpress, Google Docs and wikis are insufficient to present information in easy consumable ways, missing little things like spanned columns.)

Terms, which are defined further in the Access for All specifications and the best practices guide, used on this page include the following. Note that [there is a great web accessibility page that describes these terms|http://webaim.org/techniques/captions/] in much more detail, as well as in a [small summary on our page|a11ymetadata:Caption Transcript Audio Description Definitions].  {color:#000000}You can also view a spreadsheet of all the possible terms, in this{color} [glossary|^Accessibility Metadata Glossary.xlsx].
| auditory | Pure audio, audio with captions, video as media without primary visual content. \\ | <meta itemprop="accessMode" content="auditory"/> \\ |
| visual | While one may think that visual should be used if it's the method to get sign language or alternative text out, it's there for the adaptation only. It should not be used for these special cases of audio. \\ | \\ |
|| *mediaFeature* *accessibilityFeature* || *use as many as relevant* || ||
| captions | has captions timed to text (may require the object type to be video unless other display technology used, in which case the schema.org object type would be webApplication) | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="captions"/> |
| transcript | {color:#444444}text alternative in separate doc or pane that is not timed to the audio{color} | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="transcript"/> |
| signLanguage | requires object type to be video | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="signLanguage"/> |
|| *accessibilityHazard* || *optional as relevant* || ||
| sound | loud, repetitive sounds that can cause seizures are present | <meta itemprop="accessibilityHazard" content="sound"/> |


{code:lang=html}<div itemscope=”” itemtype=”http://schema.org/audioObject”>
<meta itemprop=”accessMode” content=”auditory”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”transcript”/>
</div>{code}

{code:lang=html}<div itemscope=”” itemtype=”http://schema.org/videoObject”>
<meta itemprop=”accessMode” content=”auditory”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”captions”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”signLanguage”/>
</div>{code}

| visual \\ | | <meta itemprop="accessMode" content="visual"/> |
| auditory \\ | the video has audio track \\ | <meta itemprop="accessMode" content="auditory"/> |
|| mediaFeature accessibilityFeature \\ || use as many as relevant \\ || ||
| captions \\ | captions are available for audio and visual content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="captions"/> \\ |
| audioDescription \\ | audio begins before visuals or pauses visuals in the middle | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="audioDescription"/> \\ |
| transcript \\ | a transcript of the video is provided in a separate pane \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="transcript"/> \\ |
|| *accessibilityHazards* || *optional as relevant* \\ || ||
| flashing \\ | rates of flashing faster than 3Hz (3 times per second) which can cause seizures are present \\ | <meta itemprop="accessibilityHazard" content="flashing"/> \\ |
| sound \\ | loud, repetitive sounds that can cause seizures are present \\ | <meta itemprop="accessibilityHazard" content="sound"/> \\ |
| motionSimulation \\ | nausea can be caused by motion simulations \\ | <meta itemprop="accessibilityHazard" content="motionSimulation"/> \\ |

h4. Video Examples
<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”accessMode” content=”auditory”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”audioDescription”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”captions”/>
</div>{code}

<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”accessMode” content=”auditory”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”captions”/>
<meta itemprop=”accessibilityHazard” content=”flashing”/>
</div>{code}

| colorDependent \\ | requires the ability to distinguish color \\ | <meta itemprop="accessMode" content="colorDependent"/> \\ |
| textOnImage \\ | There is text in the image, and may not be legible at larger scales due to pixelation, or by text-to-speech software \\ | <meta itemprop="accessMode" content="textOnImage"/> \\ |
|| *mediaFeature* *accessibilityFeature* || *use as many as relevant* \\ || ||
| alternativeText \\ | alternative text is provided for visual content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="alternativeText"/> \\ |
| audioDescription | audio description of the image is available \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="audioDescription"/> \\ |
| largePrint | resource is formatted for large print reading | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="largePrint"/> \\ |
| tactileGraphic \\ | image can be conveyed through touch, though it is not the primary method (this should conform to the [BANA guidelines and standards for tactile graphics|http://www.brailleauthority.org/tg/index.html]) \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="tactileGraphic"/> \\ |
| tactileObject \\ | the image is a picture of a 3D object, which can be expressed by a 3D model or build instructions | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="tactileObject"/> \\ |
| highContrast \\ | high contrast options are provided \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="highContrast"/> \\ |
| longDescription \\ | text descriptions are provided for image-based content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="longDescription"/> \\ |

h4. Visual Media Examples
{code:lang=html}<div itemscope=”” itemtype=”http://schema.org/imageobject”>
<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”audioDescription”/>
</div>{code}

<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”accessMode” content=”colorDependent”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”longDescription”/>
</div>{code}

{code:lang=html}<div itemscope=”” itemtype=”http://schema.org/map”>
<meta itemprop=”accessMode” content=”tactile”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”tactileGraphic”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”braille”/>
</div>{code}
{anchor:HTML}
| textual \\ | | <meta itemprop="accessMode" content="textual"/> \\ |
| visual \\ | The document includes images that are integral to the comprehension of the subject matter \\ | <meta itemprop="accessMode" content="visual"/> \\ |
|| mediaFeature accessibilityFeature \\ || use as many as relevant \\ || ||
| alternativeText \\ | alternative text is provided for visual content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="alternativeText"/> \\ |
| longDescription | descriptions are provided for image-based content and/or complex structures such as tables \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="longDescription"/> \\ |
| ChemML | chemistry equations and formulas are provided in ChemML format \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="ChemML"/> |
| MathML | math content is provided in MathML format \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="MathML"/> |
| structuralNavigation \\ | resource provides a table of contents or similar resource to allow higher-level document navigation | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="structuralNavigation"/> |
| displayTransformability \\ | aspects of the rendering can be controlled by the user \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="displayTransformabilty"/> |
| describedMath \\ | descriptions are provided for math content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="describedMath"/> |

h4. HTML Document Example
<meta itemprop=”accessMode” content=”textual”/>
<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”alternativeText”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”displayTransformability”/>
</div>{code}

| colorDependent \\ | requires the ability to distinguish color | <meta itemprop="accessMode" content="colorDependent"/> \\ |
| textOnImage \\ | There is text in the image, and may not be legible at larger scales due to pixelation, or by text-to-speech software | <meta itemprop="accessMode" content="textOnImage"/> |
|| mediaFeature accessibilityFeature \\ || use as many as relevant \\ || ||
| alternativeText \\ | alternative text is provided for visual content | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="alternativeText"/> \\ |
| longDescription \\ | text descriptions are provided for image-based content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="longDescription"/> \\ |
|| controlFlexibility \\ || use as relevant (can be multiple) \\ || \\ ||
| fullKeyboardControl \\ | can be used solely with the keyboard control and still have complete control | <meta itemprop="controlFlexibility" content="fullKeyboardControl"/> |
| textOnImage \\ | document includes scanned images of text \\ | <meta itemprop="accessMode" content="textOnImage"/> |
| colorDependent \\ | requires the ability to distinguish color | <meta itemprop="accessMode" content="colorDependent"/> |
|| mediaFeature accessibilityFeature \\ || use as relevant \\ || ||
| alternativeText | | | alternative text is provided for visual content&nbsp; \\ | | \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="alternativeText"/> \\ |
| longDescription \\ | text descriptions are provided for image-based content | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="longDescription"/> |

h4. Text Document example
| textOnImage \\ | document includes scanned images of text \\ | <meta itemprop="accessMode" content="textOnImage"/> |
| colorDependent \\ | requires the ability to distinguish color | <meta itemprop="accessMode" content="colorDependent"/> |
|| mediaFeature accessibilityFeature \\ || use as relevant \\ || ||
| alternativeText \\ | short text descriptions are provided for image-based content | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="alternativeText"/> |
| displayTransformatibility \\ | used when the document is a tagged PDF so that the content can be reflowed | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="displayTransformability"/> |

h4. PDF example
<meta itemprop=”accessMode” content=”textual”/>
<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”longDescription”/>
</div>{code}

| colorDependent \\ | information on the page requires the ability to distinguish color | <meta itemprop="accessMode" content="colorDependent"/> |
| textOnImage \\ | There is text in graphics in the book, which may not be readable by text-to-speech software | <meta itemprop="accessMode" content="textOnImage"/> |
|| mediaFeature accessibilityFeature || use as many as relevant \\ || ||
| alternativeText \\ | alternative text is provided for visual content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="alternativeText"/> \\ |
| braille | braille content or alternative is available (e.g., eBraille or print braille) | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="braille"/> |
| highContrast | high contrast options are provided | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="highContrast"/> |
| largePrint \\ | resource is formatted for large print reading | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="largePrint"/> |
| longDescription \\ | text descriptions are provided for image-based content \\ | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="longDescription"/> \\ |
| MathML, ChemML, Latex | | |
| nemethBraille \\ | math content is available in [Nemeth braille format|http://en.wikipedia.org/wiki/Nemeth_Braille] | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="nemethBraille"/> |
| musicBraille \\ | {color:#000000}music content is available in{color} {color:#000000}[music braille format|http://www.braillebug.org/music_braille.asp]{color} | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="musicBraille"/> |
| musicLargePrint | music is formatted for large print reading | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="musicLargePrint"/> \\ |

h4. Physical Book/Magazine examples
<meta itemprop=”accessMode” content=”visual”/>
<meta itemprop=”accessMode” content=”colorDependent”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”largePrint”/>
</div>{code}

{code:lang=html}<div itemscope=”” itemtype=”http://schema.org/Book”>
<meta itemprop=”accessMode” content=”tactile”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”braille”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”nemethBraille”/>
</div>{code}

{code:lang=html}<div itemscope=”” itemtype=”http://schema.org/Book”>
<meta itemprop=”accessMode” content=”tactile”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”braille”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”nemethBraille”/>
<meta itemprop=”bookFormat” content=”EBook”/>
</div>{code}
| 78 | A201 | DAISY 2: full audio with title only (no navigation) | Deprecated, as does not meet DAISY 2 standard. Use conventional audiobook codes instead. | see Audio Media \\ |
| 78 | A202 | DAISY 2: full audio with navigation (no text) | &nbsp; | see Audio Media \\
mediaFeature:structualNavigation accessibilityFeature:structualNavigation \\ |
| 78 | A203 | DAISY 2: full audio with navigation and partial text | &nbsp; | see Audio Media \\
accessMode: auditory \\
| 78 | A204 | DAISY 2: full audio with navigation and full text | &nbsp; | see Audio Media \\
accessMode:textual \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |
| 78 | A205 | DAISY 2: full text with navigation and partial audio | Reading systems may provide full audio via text-to-speech. | {color:#000000}See Book{color}\\ {color:#000000}mediaFeature:structuralNavigation{color}\\ {color:#000000}accessibilityFeature:structuralNavigation{color}\\ |
| 78 | A206 | DAISY 2: full text with navigation and no audio | Reading systems may provide full audio via text-to-speech. | see Book \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |
| 78 | A207 | DAISY 3: full audio with title only (no navigation) | Deprecated, as does not meet DAISY 3 standard. Use conventional audiobook codes instead. | see Audio Media \\ |
| 78 | A208 | DAISY 3: full audio with navigation (no text) | &nbsp; | see Audio Media \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |
| 78 | A209 | DAISY 3: full audio with navigation and partial text | &nbsp; | see Audio Media \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |
| 78 | A210 | DAISY 3: full audio with navigation and full text | &nbsp; | see Book \\
accessMode:textual \\
accessMode:auditory \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |
| 78 | A211 | DAISY 3: full text with navigation and some audio | Reading systems may provide full audio via text-to-speech. | see Book \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |
| 78 | A212 | DAISY 3: full text with navigation (no audio) | Reading systems may provide full audio via text-to-speech. | see Book \\
mediaFeature:structuralNavigation accessibilityFeature:structuralNavigation \\ |


| textual \\ | information is conveyed through text \\ | <meta itemprop="accessMode" content="textual"/> |
| visual \\ | information is conveyed through sight \\ | <meta itemprop="accessMode" content="visual"/> |
|| mediaFeature accessibilityFeature \\ || use as many as relevant \\ || ||
| braille \\ | braille content or alternative is available (e.g., eBraille or print braille) | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="braille"/> |
| tactileGraphic \\ | tactile graphics are provided | <meta itemprop="mediaFeature" itemprop="accessibilityFeature" content="tactileGraphic"/> |

h4. Tactile examples
<meta itemprop=”accessMode” content=”tactile”/>
<meta itemprop=”accessMode” content=”textual”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”tactileObject”/>
<meta itemprop=”mediaFeature” itemprop=”accessibilityFeature” content=”braille”/>
</div>{code}
(note that we considered doing this as "Sculpture" instead of ImageObject, but this is not indexed well by search engines today. Since you can either describe the object, or the image that shows the object, sculpture or imageobject could be the right thing).